Association of Treatment Duration and Clinical Outcomes in Dry Eye Treatment with Sutureless Cryopreserved Amniotic Membrane.

Background: While sutureless, cryopreserved amniotic membrane (cAM) has been shown to significantly improve signs and symptoms of dry eye disease (DED), no studies have assessed the association of cAM treatment duration to the differential response in clinical outcomes. Methods: A multi-center, retrospective study was conducted on patients with moderate-to-severe DED who were treated with self-retained cAM (Prokera® Slim) for 2 to 7 days. The primary outcome measure was DEWS severity score assessed at 1 week, 1 month, and 3 months. Secondary outcome measures included ocular discomfort, visual symptoms, corneal staining, and visual acuity. Results: A total of 89 eyes (77 patients) with moderate-to-severe DED (DEWS severity 3.24 ± 0.56) received treatment with self-retained cAM for 2 days (n = 10), 3 days (n = 15), 4 days (n = 12), 5 days (n = 19), 6 days (n = 6), or 7 days (n = 27). DEWS scores significantly improved at 1 week, 1 month, and 3 months for all treatment duration groups, with no significant difference observed between groups at any timepoint. In addition to an improvement in DEWS severity scores, those receiving cAM treatment for 2 days demonstrated a significant improvement in corneal staining, visual symptoms, and ocular discomfort at 1 week, 1 month, and 3 months. Conclusion: This retrospective study suggests that a single placement of self-retained cAM for 2 days can significantly improve signs and symptoms of DED with a lasting benefit observed for up to 3 months.

Treatment outcomes in the DRy Eye Amniotic Membrane (DREAM) study.

PURPOSE: To evaluate the efficacy of cryopreserved amniotic membrane (CAM) in reducing signs and symptoms of dry eye disease (DED) in a large patient population. METHODS: A retrospective chart review at 10 clinical sites was done of patients with refractory DED who received CAM and completed at least 3 months of follow-up. Data collected were demographics; medical history including previous and current ocular treatment, diagnosis, clinical presentations, comorbidity, duration and frequency of treatment with CAM; and concomitant medications. The primary outcome was the change in dry eye workshop (DEWS) score after treatment. RESULTS: A total of 97 eyes of 84 patients exhibited severe dry eye despite maximal medical treatments including topical artificial tears, cyclosporine-A, serum, antibiotics, and steroids. Patients manifested with superficial punctate keratitis (86%), filamentary keratitis (13%), exposure keratitis (19%), neurotrophic keratitis (2%), and corneal epithelial defect (7%). After CAM treatment for 5.4±2.8 days, 74 (88%) patients demonstrated an improved ocular surface along with a notable reduction of the severity as the overall DEWS score was significantly reduced from 3.25±0.5 at baseline to 1.44±0.6 at 1 week, 1.45±0.6 at 1 month, and 1.47±0.6 at 3 months (p<0.001). Ten eyes (10%) required repeated treatment to complete healing. Apart from discomfort during CAM placement, there were no adverse events. CONCLUSION: Placement of CAM is promising to enhance the recovery of ocular surface health and reduce signs and symptoms in patients with moderate-to-severe DED.

Prospective evaluation of intraocular lens calculation after myopic refractive surgery.

PURPOSE: To evaluate outcome after refractive surgery in cataract patients for whom intraocular lens (IOL) selection was based on the use of a myopic regression formula. METHODS: This prospective case series included 20 eyes of 14 patients who had previous uncomplicated myopic refractive surgery, followed by uncomplicated cataract extraction with IOL implantation. Calculation of IOL was based on flattest keratometry readings, spherical equivalent refraction before refractive surgery, and an adjustment factor derived from the regression formula: -(0.47x + 0.85). Following cataract extraction, refractive error was compared against refractive aim. The power of IOL obtained by the regression formula (IOL(RF)) was compared to those obtained using the clinical history method at the spectacle plane (IOL(HisKs)) and the Double-K formula (LOL(DoubleK)). The results acquired with each technique were compared with those achieved using an IOL back-calculated for emmetropia (IOL(exact)). RESULTS: Using the regression formula, IOL calculations produced postoperative cataract extraction refractions within 1.00 diopter (D) (range: -1.00 to 0.78 D) of the intended outcome. Mean spherical equivalent refraction after cataract extraction was -0.31 +/- 0.56 D. Twelve of 20 eyes had sufficient data to evaluate the statistical relationships among the three formulas compared with IOL(exact). Paired t test results revealed IOL(RF) (P = .0932) and IOL(HisKs) (P = .9955) were not statistically different from IOL(exact) whereas IOL(DoubleK) was statistically different from IOL(exact) (P = .0008). CONCLUSIONS: The myopic regression formula is recommended for postoperative myopic LASIK IOL selection to provide a simple, accurate, and consistent method of predicting IOL calculation that is not statistically different from IOL(exact).

Complications of AlphaCor keratoprosthesis: a clinicopathologic report.

PURPOSE: To describe the clinical and histopathologic features of intractable secondary glaucoma induced by AlphaCor keratoprosthesis. METHODS: An elderly woman with pseudoexfoliation glaucoma and pseudophakic bullous keratopathy in the right eye had graft failures after penetrating keratoplasty. Her best-corrected visual acuity at presentation was counting fingers in the right eye and 20/30 in the left eye. Examination showed severe corneal neovascularization. Chirila keratoprosthesis type II was implanted in 2 stages. Ten months later, the patient developed dense retrocorneal membrane, 360 degrees occlusion of angles, intractable glaucoma, no light perception, and nasal stromal melting associated with partial extrusion of the keratoprosthesis. RESULTS: Histopathology revealed invasion of the porous material of the keratoprosthesis by reactive fibroblasts and multinucleated foreign-body giant cells. In the area of dehiscence, we noted thinning and lysis of the collagen fibers, infiltration of lymphocytes, and plasma cells with a sheet of fibroinflammatory tissue extending into the anterior chamber. CONCLUSIONS: Corneal stromal melting and retrocorneal prosthetic membrane formation after AlphaCor keratoprosthesis implantation led to intractable glaucoma and extrusion of the implant.

Intraocular lens calculations after hyperopic refractive surgery.

PURPOSE: To evaluate the effect of hyperopic refractive surgery on intraocular lens (IOL) power calculation, compare published methods of IOL power calculation after refractive surgery, evaluate the effect of prerefractive surgery refractive error on IOL deviation, and introduce a new alternative formula for IOL calculation in patients who have had refractive surgery for hyperopia. DESIGN: Retrospective noncomparative case series. PARTICIPANTS: Twenty eyes from 13 patients who had undergone cataract surgery after previous hyperopic refractive surgery. METHODS: Seven different methods of IOL calculation were performed retrospectively: clinical history (IOL(hisK)), clinical history method at spectacle plane (IOL(hisKs)), vertex (IOL(vertex)), back calculated (IOL(BC)), calculation based on average keratometry (IOL(avgK)), calculation based on steepest keratometry (IOL(steepK)), and calculation based on the double K formula (IOL(doubleK)). Each method's result was compared with an exact IOL (IOL(exact)), which would have resulted in emmetropia. Each method was then compared with change in spherical equivalent induced by refractive surgery (SE(h)). A paired t test was used to determine statistical significance. MAIN OUTCOME MEASURE: Mean error in IOL power prediction for each method when compared to IOL(exact). RESULTS: When evaluating different methods of IOL calculations, IOL(vertex) was the most accurate, with a mean deviation from emmetropia of 0.42+/-1.75 diopters (D), followed by IOL(BC) (+0.54+/-1.86 D), IOL(hisK) (+1.56+/-2.35 D), IOL(hisKs) (+1.57+/-2.35 D), IOL(steepK) (+1.59+/-2.25 D), IOL(doubleK) (+1.65+/-2.56 D), and IOL(avgK) (+2.24+/-2.46 D). There was no statistical difference between IOL(vertex), IOL(BC), and IOL(exact). The power of IOL(avgK) would be inaccurate by 0.27x+1.53, where x = SE(h). Thus, most patients without the adjustment to IOL(avgK) would be left myopic. However, when IOL(avgK) is adjusted with this formula, there is no statistical difference to IOL(exact). CONCLUSIONS: For IOL power selection in previously hyperopic patients, a predictive formula based only on SE(h) and current average keratometry readings was not found to statistically differ from IOL(exact). The IOL(vertex) and IOL(BC), which also did not statistically differ from IOL(exact), require prerefractive surgery keratometry readings that are often not available to the cataract surgeon.

Intraocular lens calculations after refractive surgery.

PURPOSE: To evaluate the effect of refractive surgery on intraocular lens (IOL) power calculation, compare methods of IOL power calculation after refractive surgery, evaluate the effect of pre-refractive surgery refractive error on IOL deviation, review the literature on determining IOL power after refractive surgery, and introduce a formula for IOL calculation for use after refractive surgery for myopia. SETTING: Laser & Corneal Surgery Associates and Center for Ocular Tear Film Disorders, New York, New York, USA. METHODS: This retrospective noncomparative case series comprised 21 patients who had uneventful cataract extraction and IOL implantation after previous uneventful myopic refractive surgery. Six methods of IOL calculation were used: clinical history (IOL(HisK)), clinical history at the spectacle plane (IOL(HisKs)), vertex (IOL(vertex)), back-calculated (IOL(BC)), calculation based on average keratometry (IOL(avgK)), and calculation based on flattest keratometry (IOL(flatK)). Each method result was compared to an "exact" IOL (IOL(exact)) that would have resulted in emmetropia and then compared to the pre-refractive surgery manifest refraction using linear regression. The paired t test was used to determine statistical significance. RESULTS: The IOL(HisKs) was the most accurate method for IOL calculations, with a mean deviation from emmetropia of -0.56 diopter +/-1.59 (D), followed by the IOL(BC) (+1.06 +/- 1.51 D), IOL(vertex) (+1.51 +/- 1.95 D), IOL(flatK) (-1.72 +/- 2.19 D), IOL(HisK) (-1.76 +/- 1.76 D), and IOL(avgK) (-2.32 +/- 2.36 D). There was no statistical difference between IOL(HisKs) and IOL(exact) in myopic eyes. The power of IOL(flatK) would be inaccurate by -(0.47x+0.85), where x is the pre-refractive surgery myopic SE (SEQ(m)). Thus, without adjusting IOL(flatK), most patients would be left hyperopic. However, when IOL(flatK) is adjusted with this formula, it would not be statistically different from IOL(exact). CONCLUSIONS: For IOL power selection in previously myopic patients, a predictive formula to calculate IOL power based only on the pre-refractive surgery SEQ(m) and current flattest keratometry readings was not statistically different from IOL(exact). The IOL(HisKs), which was also not statistically different from IOL(exact), requires pre-refractive surgery keratometry readings that are often not available to the cataract surgeon.